/*
 * The contents of this file are subject to the terms 
 * of the Common Development and Distribution License 
 * (the License).  You may not use this file except in
 * compliance with the License.
 * 
 * You can obtain a copy of the license at 
 * https://glassfish.dev.java.net/public/CDDLv1.0.html or
 * glassfish/bootstrap/legal/CDDLv1.0.txt.
 * See the License for the specific language governing 
 * permissions and limitations under the License.
 * 
 * When distributing Covered Code, include this CDDL 
 * Header Notice in each file and include the License file 
 * at glassfish/bootstrap/legal/CDDLv1.0.txt.  
 * If applicable, add the following below the CDDL Header, 
 * with the fields enclosed by brackets [] replaced by
 * you own identifying information: 
 * "Portions Copyrighted [year] [name of copyright owner]"
 * 
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 */
package com.sun.appserv.management.util.jmx;

import java.util.Map;
import java.util.Set;
import java.util.HashMap;
import java.util.Date;
import java.util.Iterator;
import java.util.Collection;
import java.io.Serializable;

import java.math.BigInteger;
import java.math.BigDecimal;

import java.lang.reflect.Array;

import javax.management.ObjectName;
import javax.management.openmbean.OpenType;
import javax.management.openmbean.ArrayType;
import javax.management.openmbean.CompositeData;
import javax.management.openmbean.CompositeDataSupport;
import javax.management.openmbean.CompositeType;
import javax.management.openmbean.TabularType;
import javax.management.openmbean.TabularData;
import javax.management.openmbean.SimpleType;
import javax.management.openmbean.OpenDataException;
import javax.management.openmbean.InvalidOpenTypeException;

import com.sun.appserv.management.util.misc.ArrayConversion;
import com.sun.appserv.management.util.misc.IteratorUtil;
import com.sun.appserv.management.util.misc.TypeCast;

/**
	Utilities dealing with OpenMBeans
 */
public final class OpenMBeanUtil
{
	private OpenMBeanUtil()		{}
	
	private static Map<Class,SimpleType>	SIMPLETYPES_MAP	= null;
		private static Map<Class,SimpleType>
	getSimpleTypesMap()
	{
		if ( SIMPLETYPES_MAP == null )
		{
			final Map<Class,SimpleType> m	= new HashMap<Class,SimpleType>();
			
			m.put( Byte.class, SimpleType.BYTE );
			m.put( Short.class, SimpleType.SHORT );
			m.put( Integer.class, SimpleType.INTEGER );
			m.put( Long.class, SimpleType.LONG );
			m.put( BigInteger.class, SimpleType.BIGINTEGER );
			m.put( BigDecimal.class, SimpleType.BIGDECIMAL );
			m.put( Float.class, SimpleType.FLOAT );
			m.put( Double.class, SimpleType.DOUBLE );
			
			m.put( Character.class, SimpleType.CHARACTER );
			m.put( Boolean.class, SimpleType.BOOLEAN );
			m.put( String.class, SimpleType.STRING );
			m.put( Date.class, SimpleType.DATE );
			m.put( Void.class, SimpleType.VOID );
			
			m.put( ObjectName.class, SimpleType.OBJECTNAME );
			
			SIMPLETYPES_MAP	= m;
		}
		
		return( SIMPLETYPES_MAP );
	}
	
	/**
		Get the SimpleType for a class which can be so-represented.
	 */
		static public SimpleType
	getSimpleType( final Class c )
	{
		final SimpleType	type	= (SimpleType)(getSimpleTypesMap().get( c ));
		
		return( type );

	}
	
	private static final String[]	EMPTY_STRING_ARRAY	= new String[ 0 ];
	private static final OpenType[]	EMPTY_OPENTYPES		= new OpenType[ 0 ];
	

	
	/**
		Get any non-null array element from the array.
	 */
		private static Object
	getAnyArrayElement( Object o )
	{
		Object	result	= null;
	
		final int	length	= Array.getLength( o );
		if ( length != 0 )
		{
			for( int i = 0; i < length; ++i )
			{
				final Object	element	= Array.get( o, 0 );
				
				if ( element != null )
				{
					if ( element.getClass().isArray() )
					{
						result	= getAnyArrayElement( element );
						if ( result != null )
							break;
					}
					else
					{
						result	= element;
						break;
					}
				}
			}
		}
		
		return( result );
	}
	
	
		private static int
	getArrayDimensions( final Class theClass )
	{
		final String	classname	= theClass.getName();
		
		int	dim	= 0;
		while ( classname.charAt( dim ) == '[' )
		{
			++dim;
		}
		
		return( dim );
	}
	
	
	/**
		Get the OpenType of an Object, which must conform to OpenType requirements.
	 */
		static public OpenType
	getOpenType( final Object o )
		throws InvalidOpenTypeException, OpenDataException
	{
		if ( o == null )
		{
			// no OpenType for a null
			throw new IllegalArgumentException();
		}
		
		OpenType	type	= getSimpleType( o.getClass() );
		
		if ( type == null )
		{
			final Class	theClass	= o.getClass();
			
			if ( theClass.isArray() )
			{
				final int		length		= Array.getLength( o );
				final int		dimensions	= getArrayDimensions( theClass );
				final Class		elementClass	= theClass.getComponentType();
				
				final SimpleType	simpleType	= getSimpleType( elementClass );
				if ( simpleType != null )
				{
					type	= new ArrayType( dimensions, simpleType );
				}
				else
				{
					final Object	element	= getAnyArrayElement( o );
					
					if ( CompositeData.class.isAssignableFrom( elementClass ) )
					{
						if ( element == null )
						{
							type	= SimpleType.VOID;
						}
						else
						{
							type	= new ArrayType( dimensions, ((CompositeData)element).getCompositeType() );
						}
					}
					else if ( TabularData.class.isAssignableFrom( elementClass ) )
					{
						if ( element == null )
						{
							type	= SimpleType.VOID;
						}
						else
						{
							type	= new ArrayType( dimensions, ((TabularData)element).getTabularType() );
						}
					}
				}
				
			}
			else if ( o instanceof CompositeData )
			{
				type	= ((CompositeData)o).getCompositeType();
			}
			else if ( o instanceof TabularData )
			{
				type	= ((TabularData)o).getTabularType();
			}
		}
		
		if ( type == null )
		{
			throw new IllegalArgumentException( o.getClass().getName() );
		}
		
		return( type );
	}
	
	/**
		Convert certain types and return a new Map:
		<ul>
		<li>Collection converts to an array</li>
		</ul>
		Nulls are not eliminated; use
		{@link com.sun.appserv.management.util.misc.MapUtil#newMapNoNullValues} to
		do that before or after.
	 */
		public static Map<String,Serializable>
	convertTypes( final Map<String,Serializable> orig )
	{
		final Map<String,Serializable>
		    result	= new HashMap<String,Serializable>();
		
		for( final String key : orig.keySet() )
		{
			final Serializable	value	= (Serializable)orig.get( key );
			
			if ( value instanceof Collection )
			{
				Object[]	newValue	=
					IteratorUtil.toArray( ((Collection<Serializable>)value).iterator() );
				newValue	= ArrayConversion.specializeArray( newValue );
				
				result.put( key, newValue );
			}
			else
			{
				result.put( key, value );
			}
		}
		
		
		return( result );
	}
	
	/**
		Create a CompositeType from a Map.  Each key in the map must be a String,
		and each value must be a type consistent with OpenTypes.
		
		@param typeName	the arbitrary name of the OpenType to be used
		@param description	the arbitrary description of the OpenType to be used
		@param map	a Map keyed by String, whose values may not be null
	 */
		public static CompositeType
	mapToCompositeType(
		final String	typeName,
		final String	description,
		final Map<String,?>		map,
		CompositeTypeFromNameCallback   callback)
		throws OpenDataException
	{
		final String[]		itemNames	= new String[ map.keySet().size()];
		map.keySet().toArray( itemNames );
		
		final String[]		itemDescriptions	= new String[ itemNames.length ];
		final OpenType[]	itemTypes			= new OpenType[ itemNames.length ];
		
		for( int i = 0; i < itemNames.length; ++i )
		{
		    final String    name    = itemNames[ i ];
			final Object	value	= map.get( name );
			
			itemDescriptions[ i ]	= "value " + name;
			if ( value == null )
			{
				// force nulls to type String
				itemTypes[ i ]	= callback.getOpenTypeFromName( name );
			}
			else
			{
				itemTypes[ i ]			= getOpenType( value );
			}
		}
		
		final CompositeType		type	= new CompositeType(
								typeName,
								description,
								itemNames,
								itemDescriptions,
								itemTypes );
	
		return( type );
	}
	
	/**
		Create a CompositeData from a Map.  Each key in the map must be a String,
		and each value must be a type consistent with OpenTypes.
		
		@param typeName	the arbitrary name of the OpenType to be used
		@param description	the arbitrary description of the OpenType to be used
		@param map	a Map keyed by String, whose values may not be null
	 */
		public static CompositeData
	mapToCompositeData(
		final String	typeName,
		final String	description,
		final Map<String,Object> map )
		throws OpenDataException
	{
		final CompositeType	type	= mapToCompositeType( typeName, description, map, null);
		
		return( new CompositeDataSupport( type, map ) );
	}
	
	
	/**
		Convert a CompositeData to a Map.
	 */
		public static Map<String,Serializable>
	compositeDataToMap( final CompositeData data )
	{
		final Map<String,Serializable>		map	= new HashMap<String,Serializable>();
		final CompositeType		type	= data.getCompositeType();
		final Set<String>   keySet  = TypeCast.asSet( type.keySet() );
		
		for( String name : keySet )
		{
			map.put( name, (Serializable)data.get( name ) );
		}
		
		return( map );
	}
	
	
		
	/**
		Get a CompositeType describing a CompositeData which has no elements.
	 */
		public static OpenType
	getStackTraceElementOpenType()
		throws OpenDataException
	{
		final String[]	itemNames	= new String[]
		{
			"ClassName",
			"FileName",
			"LineNumber",
			"IsNativeMethod",
		};
		
		final String[]	descriptions	= new String[  ]
		{
			"ClassName",
			"FileName",
			"LineNumber",
			"IsNativeMethod",
		};
		
		final OpenType[]	openTypes	= new OpenType[ itemNames.length ];
		openTypes[ 0 ]	= SimpleType.STRING;
		openTypes[ 1 ]	= SimpleType.STRING;
		openTypes[ 2 ]	= SimpleType.INTEGER;
		openTypes[ 3 ]	= SimpleType.BOOLEAN;
		
		return( new CompositeType(
			StackTraceElement.class.getName(), 
			"StackTraceElement composite type",
			itemNames,
			descriptions,
			openTypes
			) );
	}
	
	/**
		Get a CompositeType describing a CompositeData which has no elements.
	 */
		public static OpenType
	getThrowableOpenType( final Throwable t)
		throws OpenDataException
	{
		final String[]	itemNames	= new String[]
		{
			"Message",
			"Cause",
			"StackTrace",
		};
		
		final String[]	descriptions	= new String[  ]
		{
			"The message from the Throwable",
			"The cause (if any) from the Throwable",
			"The stack trace from the Throwable",
		};
		
		final OpenType[]	openTypes	= new OpenType[ itemNames.length ];
		
		openTypes[ 0 ]	= SimpleType.STRING;
		openTypes[ 1 ]	= t.getCause() == null ? SimpleType.VOID : getThrowableOpenType( t.getCause() );
		openTypes[ 2 ]	= new ArrayType( t.getStackTrace().length,
							getStackTraceElementOpenType() );
		
		
		return( new CompositeType(
			t.getClass().getName(), 
			"Throwable composite type",
			itemNames,
			descriptions,
			openTypes
			) );
	}
	
}






